Partial support is requested to upgrade NMR spectrometers located in the National Magnetic Resonance Facility at Madison (NMRFAM). The spectrometer systems currently have AM consoles (circa 1985 technology). These are to be replaced by consoles that represent the state-of-the-art. The present consoles make it difficult or impossible to carry out newer multinuclear, multidimensional NMR experiments. The upgrades will include new probes with improved temperature uniformity across the sample, larger probes for dealing with less-soluble samples or for obtaining more accurate cross-relaxation data, and field gradient probes for optimal solvent suppression. The upgrades will benefit a large number of ongoing projects (several supported by the NIH) and will increase the research effectiveness of the NIH-supported facility as a whole. Each of the major user groups has considerable prior NMR expertise or is collaborating with staff members of NMRFAM. The instruments will be housed in the NMR facility and will be maintained by the staff of the NMR facility who are supported in part by University funds. NMRFAM staff members will train users to operate the upgraded equipment.